Coexistence of myasthenia gravis with hypokalemic periodic paralysis: a rare presentation.

Bilateral symmetrical weakness of acute onset is not very uncommon and the differential varies widely from life-threatening neurological illnesses to metabolic and electrolyte derangements. We report the case of a young female with severe muscle weakness, respiratory distress and hypokalemia who required immediate intubation on arrival to emergency department. During hospital course, even after normalisation of serum potassium and some improvement in limb weakness, patient failed multiple attempts of extubation because of type II respiratory failure. Subsequently, acetyl cholinesterase antibodies were checked which came out positive, and diagnosis of myasthenia gravis and hypokalemic periodic paralysis was made. She was successfully extubated after intravenous pulse steroids, pyridostigmine and plasmapheresis. Patient was finally discharged home on oral steroids, pyridostigmine and azathioprine. In a patient presenting with hypokalemic weakness, the suspicion of a second disorder should be very high if weakness fails to resolve following correction of hypokalemia.